The present invention relates to an improved rotary type railroad car coupler assembly. More particularly, the invention relates to such an assembly having increased service life and effectiveness.
Rotary type railroad car coupler assemblies are conventionally used in associated with railroad cars employed in rotary dump service where the rotating car remains coupled to the immediately adjacent cars. The railroad cars provided for this application are generally equipped with a rotary type coupler at one end and a stationary coupler at the other end. Each rotary coupler must therefore be capable of rotating with respect to the car on which it is mounted. Known rotary couplers are disclosed, for example, in U.S. Pat. Nos. 2,973,104; 2,973,105; 2,990,962 and 2,990,963.
As can be expected, several components within the rotary coupler assembly are subject to wear, and therefore, to periodic replacement. One element which is particularly prone to wear is the yoke collar. The rotary type coupler includes a shank which is attached to the car by being pinned to the yoke collar associated with a draft gear. This yoke collar bears against a yoke during a draft condition thereby transmitting draft forces from the coupler shank to the yoke, striker and car sill, as will be described in detail hereinafter. In any event, the yoke collar is subject to wear which eventually results in excessive slack in coupler operation and requires yoke collar replacement. Improved yoke collar service life and effectiveness are clearly desirable.
Therefore, one object of the present invention is to provide an improved rotary type railroad car coupler assembly.
Another object of the present invention is to provide a rotary type railroad car coupler assembly with a yoke collar having an increased service life.
A still further object of the present invention is to provide a rotary type railroad car coupler assembly having improved ease of maintenance and serviceability, e.g. inspection, lubrication and the like. Other objects and advantages of the present invention will become apparent hereinafter.
An improved rotary type railroad car coupler assembly has now been discovered. The coupler assembly comprises a railroad car sill, a striker secured to the sill, a coupler having a head and a shank, a draft gear and a yoke positioned so as to act in concert with the draft gear and sill to transmit draft and buff forces from the coupler to a body of the railroad car. The yoke is symmetrical and therefore invertible and has a substantially cylindrical cavity portion within which is disposed a yoke collar. This yoke collar, preferably substantially cylindrical in configuration, has two substantially opposing ends and a top and a bottom wall having two substantially opposing apertures therein.
The yoke collar acts to receive at least a portion of the coupler shank and to transmit draft forces from the coupler head to the yoke. Also included is a pin connecting the yoke collar and the shank in such a manner that the yoke collar and shank are substantially free to rotate within the cavity of the yoke. The pin is snugly fitted into both of the apertures in the yoke collar.
The present improvement involves providing a yoke which is symmetrical and therefore invertible and a yoke collar which is constructed so as to be capable of being reversibly disposed within the cavity defined by the yoke. In this manner, when the amount of wear at the end of the yoke collar which bears against the yoke becomes excessive, the coupler can be disassembled and the yoke collar reversed so that the other less worn end of the yoke collar replaces the excessively worn end in frequent contact with the yoke. Likewise, the yoke may be inverted to relocate areas of wear should such occur. The invertible feature of the yoke also simplifies assembly of the coupler since the yoke has no specific top or bottom. The present invention provides for longer, e.g. about twice as long, yoke collar service life as well as reduced manufacturing costs resulting from the yoke and yoke collar having a simpler configuration.
One particularly preferred embodiment of the present invention involves a yoke collar construction in which the center point of each of the substantially opposing apertures is substantially equidistant from each of the substantially opposing ends of the yoke collar. In this embodiment, the yoke collar, pin and shank are originally assembled according to specifications and close tolerances. As the one end of the yoke collar wears from contact with the yoke, the specifications and tolerances no longer apply and excessive slack in the system is observed. At this point, the coupler assembly is disassembled, the yoke collar reversed, and put together again for services. The reversal of the yoke collar results in the system operating at or close to the original specifications and tolerances.
In another preferred embodiment, the present assembly is constructed so that the pin is capable of being inserted in or withdrawn from the substantially opposing apertures of the yoke collar through at least one hole in the sill and/or striker, preferably through holes in both the striker and the sill. This feature provides for simple application or removal of the pin without disturbing the remainder of the system. In addition, the side access hole or holes serve other purposes. For example, system components can be inspected and excessive wear of the pin, shank pin hole and yoke collar detected without removal of other components. Further, these holes provide an effective point or points to lubricate the coupler assembly.
Although the components of the present coupler assembly may have any suitable configuration, preferably the pin and the yoke collar are substantially cylindrical in configuration. In addition, the substantially opposing apertures in each sidewall of the yoke collar are preferably substantially circular in cross section.
These and other aspects and advantages of the present invention are set forth in the following detailed description and claims, particularly when considered in conjunction with the accompanying drawings in which like parts bear like reference numerals.